While I was away VirtualBox 5.2.14 was released.
I’ve done the install on my Windows 10 laptop and on my Windows 10 PC at work and both worked fine.
I also pulled down the latest version of Vagrant (2.1.2) and did a complete rebuild of some stuff. From what I can see it’s all good. 🙂
Update: I also did both upgrades on macOS and they worked fine also.